Resveratrol (3,5,4′-trihydroxystilbene, RES) is a stilbene type compound found in varying amounts and structures (e.g., trans-, cis-, glucoside (piceid) etc.), as depicted in FIG. 1, infra. Resveratrol is produced by several plants, especially in grapes. It has also been produced by chemical synthesis.
Resveratrol is a phytoalexin (chemicals generated by a plant when it is subject to external stress) and has multiple biological activities. Resveratrol provides a number of beneficial effects, including anti-cancer, anti-inflammatory, anti-bacterial, antiviral, neuroprotective, anti-aging, and life-prolonging effects.
Resveratrol interferes with all three stages of carcinogenesis—initiation, promotion and progression. Experiments in cell cultures of varied types and isolated subcellular systems in vitro imply many mechanisms in the pharmacological activity of resveratrol. These mechanisms include modulation of the transcription factor NF-kB inhibition of the cytochrome P450 isoenzyme CYP1A1, alterations in androgenic actions and expression and activity of cyclooxygenase (COX) enzymes.
Resveratrol has been shown to induce apoptosis in some lineages of cancer cell culture (see, e.g., Sareen et al., Investigative Ophthamology & Visual Science, (2006), 47:3708-16) and reduce the probability of breast cancer occurrence (Subbaramaiah et al., J. Biol. Chem., (1998), 273:21875-21882). The Chemoprevention Database reports six studies showing that small doses of dietary resveratrol can reduce colon carcinogenesis in rats and mice. Resveratrol is now under extensive investigation as a cancer chemopreventive agent.
Like many non-steroid anti-inflammatory drugs (NSAID), resveratrol has a chemically protective effect and can suppress COX-1, but will not induce action of COX-2 (cyclooxygenase-2) (see, e.g., Jang et al., Science, (1997), 275:218-220). It has also been reported that resveratrol DMSO solution could suppress the growth of bacteria Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis; as well as the growth of dermatophytes such as Trichophyton mentagrophytes and Trichophyton rubrum (Chan, Biochem. Pharmacol., (2002), 63:99-104).
Moreover, resveratrol contained in red wines is very effective in preventing cardiovascular diseases and has extraordinary antioxidation characteristics and anticarcinogenicity. Frankel et al. (Frankel et al., J. Agric Food Chem., (1995), 43:890-894) reported that trans-resveratrol can suppress the oxidation of low density lipoprotein (LDL) in human body. Studies showed that resveratrol prolongs the lifespan of the worm Caenorhabditis elegans and the fruit fly Drosophila melanogaster (Wood et al., Nature, (2004), 430:686-689). Resveratrol extended the maximum lifespan of a short-lived fish, Nothobranchius furzeri, by 59%, and extended its median lifespan by 56%. Also noted were an increase in swimming performance, an increase in cognitive performance, and a lack of neurofibrillary degeneration (Valenzano et al., Current Biology, (2006), 16:296-300). Recently, a report showed that resveratrol improves health and survival of mice on a high-calorie diet (Baur et al., Nature, 2006, 444:337-342). In addition, resveratrol was reported effective against neuronal cell dysfunction and cell death, and in theory could help against diseases such as Huntington's disease (Parker et al., Nature Genetics, (2005), 4:349-50) and Alzheimer's disease (Marambaud et al., J. Biol. Chem., (2005), 280:37377-82).
Efforts have been made to extract resveratrol from various plant sources and to promote production of resveratrol in plant cells by artificially providing stress. For example, Chung et al. (Chung et al., Mol. Cells, (2001), 12:353-9) reported that resveratrol contents in the leaves and roots of peanuts (Arachis hypogaea L. var. Jinpoong) were significantly increased when cultured in a medium containing yeast extract. Krisa et al. (Krisa et al., J. Nat. Prod., (1999), 62:1699-1690) found that addition of jasmonic acid (JA) or its derivative methyl jasmonate (MeJA) increases the resveratrol content in cultured grape cells. It was also reported that UV radiation, sucrose concentration in the culture medium, and fungal infection may result in increased resveratrol content in grapes (see, e.g., Sarig et al., Physiol. Mol. Plant Pathol., (1997), 50:337-347).
Vitis thunbergii Sieb. et Zucc. (V. thunbergii) is a plant in the grape category. The stem and twigs of V. thunbergii are a commonly used herbal medicine in Taiwan. It is believed to be effective in supplementing the kidneys, improving the eyesight, relieving rheumatic pains, removing toxins and supplementing the blood, and is mainly used to treat eye disease, rheumatism, rental deficiencies as well as lung disease, breast tumors, unknown swollenness, and hepatitis.
Many studies have been conducted on the cultivation of grape cells. Almost all the studies focused on the most common grape species of Vitis vinifera. There have been only a few studies related to tissue culture of V. thunbergii. For example, there was an attempt to use the anther of the V. thunbergii for plant regeneration, but only a small number of buds or calluses was reported to be generated from the studies. See Hirabayashi et al., HortScience, (1976), 11:511-512. There was another attempt by Mii et al., Sci. Hortic., (1991), 46:253-260, which studied the formation of calluses from the protoplast of V. labruscana and V. thunbergii in a B5 modified medium. None of these studies, however, have focused on the studies of the resveratrol contents in the in vitro tissue.